Incus, a system container and virtual machine manager, contains a flaw where instance snapshots ignore the restricted.containers.lowlevel=block configuration setting. Because low‑level hooks such as raw.lxc and raw.qemu are processed during snapshot creation, an attacker can inject malicious commands that execute on the Incus host. This allows arbitrary command execution on the underlying server, effectively compromising the entire host operating system. Based on the description, it is inferred that the attacker must have the ability to create or modify instance snapshots, which generally requires privileged or authenticated access to the Incus daemon.

The affected product is Incus under the lxc:incus project. All releases prior to version 7.2.0 are vulnerable when instance snapshots are taken, as the tool fails to enforce the restricted.containers.lowlevel=block setting. Version 7.2.0 patches the issue by restoring the enforcement of the configuration during snapshot handling.

The CVSS score of 9.9 marks the vulnerability as critical. The EPSS score of 0.00703 (i.e., < 1%) indicates a very low probability of exploitation, and the vulnerability is not listed in the CISA KEV catalog. Attackers need the ability to create or modify instance snapshots, which typically requires privileged or authenticated local access to the Incus daemon. Once this condition is met, the attacker can provide crafted hook data that triggers arbitrary command execution on the host. Based on the description, it is inferred that the attack vector hinges on the ability to create or modify instance snapshots.